Inductance-coil.



F. G. THAGKABER ff.

* INDUCTALIGE GOIL.

APPLICATION PLIBD AUG. I, 191.

Patented Dec. 9, 1913.

UNITED STATES PATENT' FFICE.

FORREST G. THACKABERRY, OF TAMPICO, ILLINOIS.

INDUCTANCE-COTL.

To all whom it may concern:

Be it known that I. l omzrsr G. TlLlUKA- nnnnr, a citizen of the United States, residing at 'lampieo. in the county of hitcside, State of Illinois, have invented certain new and useful Illll')l'0\'('l'll0llt,5 in Inductance- Coils; and I do hereby declare the following to be a full, cl air, and exact description of the invention. such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to inductance coils.

The object of the invention resides in the provision of a resistance coil which includes an improved construction whereby the resistance uttered by the coil to the circuit in which it. is included may be increased and din'iinished as circumstances may require, the coil being particularly useful in effecting the tuning ot wireless apparatus.

\Vith the abov and other objects in view the invention consists in the details of const ruction and in thv arrangement and eom bination of parts to be hereinafter more fully described and particularly pointed out in the appended claim.

In describing the invention in detail reference will be had to the accoi'n 'mnying drawings wherein like characters of refer ence denote corresponding parts in the several views, and in which Figure l is a plan view of the invention.

Fifi. 2 a side view of same... Fig. 3 a sect'ion on the. line 3 3 of Fig. 2. and Fig. 4 a partial section on the line 4 d of Fig. 'l.

referring to the drawings. the device is shown as comprising a frame A which includes a pair of spaced nd members 10 and 11. and core members '11! and 13 connecting the end members 10 and ll said core members being disposed in a co'nnnon horizontal plane. it will ot course be understood that the end members It) and inei'nbers l2 and '13 are eoi'istru ted of suit able l'nurCOndH -ling material. Mounted in the. end member 10 between the. core. mom hers 12 and 13 is a binding post 14, while another binding post. if) is similarly mounted in the end member '1]. Connecting the end members i and it above the core member 12 is a metallic rod 16, while another metallic rod 17 conne ts the'end members 10 and 11 and is disposed above the core member 13. 'l'hc. rod It; is electrically connected with the binding post: 14- by means conductor element 18, while the rod 17 is electrically Specification of Letters Patent.

Application filed August 7, 1912.

HV and the core;

: medium of the binding posts 14 and 15. If

Patented Dec. 9, 1 913.

Serial No. 713,887.

connected to the binding post 14 by means of a conductor element 19. Having one end connected to the binding post 15 is a relatively'fine insulated wire 20. This wire is wound upon the core member 12 in the desired number of layers and then extended across to the core member 13' as at 21 and then wound upon said core member 13 in the desired number of layers and terminates at 22 in spaced relation to the end n'iember 11. It will be noted that the point where the wire 20 is carried across from the core 12 to the core member 13 is disposed in spaced relati n to the end n'iember 10. Slidably mounted on the rod lti is a metallic sleeve 23, while. a corresponding metallic sleeve is slidably mounted on the. rod 17. "The insulation of the wire 20 disposed upon the core 1) is scraped oil at a point directly beneath the rod '16 so as to expose the outer side of the wire coils but not to disturb the insulation between the coils then'iselves. This exposed portion of the wire coil on the core member 12 is adapted to be engaged at. diflerent. points by a contact linger 25 carried by the sleeve 23 and adapted further to pass out of engagement with the coils when the sleeve is moved to its limit toward the end member l0. Likewise the insulation on the wire coils carried by the core member 13 .is scraped otl' directly beneath the rod 17 and this exposed portion of the coil is adapted to be engaged by a contact linger 26 carried by the sleeve 24. This contact; finger is also adapted to engage the coils on the core member 13 at (litterent. points as the sleeve 24 is adjusted on the rod 17 and further adapted to pass entirelyout of engagement with the coils on the core member l4 when the sleeve 24 has been moved to its limit on the.rod 17 toward the. end member 11.

To the operation of the device same is connected in a given circuit through the it is desired to offer the full resistance of: the coil to the current of the circuit, the sleeve 1 is adjusted to its limit of movement on the rod it; toward the end member 10, while the. sleeve 24 is adjusted to bring the contact linger EZt in i-mzagei'neiit with the wire coil nearest the end member 11 and disposed upon the. core member 13. The current will then pass through all of the coils of wire. on both the. core members l2and l3 and the maximum resistance will be offered by the device to the current. By adjusting the sleeve 24 toward the end member 10 it will be apparent that the resistance offered to the device by the current may be constantly diminished. By adjusting the sleeve Bite the limit of its movement toward the end member 11 and then adjusting the sleeve 23 so as to engage the coil on the core member 12 nearest the end member 10 it will be apparent that only the resistance of the coils on the core member 12 will'be offered to the current and this resistance can be constantly diminished by adjusting the sleeve 23 toward the end member 11.

The resistance of the device may be entirely cut out by'adjusting the sleeve 23 to the limit of its movement .toward the end member 10 and thesleeve 24 to the limit of its movement toward the end mem- 'ber 11. In this last named position of the sleeves 23 and 24 the'device will serve as an eflicient lightning arrester and thereby protect the apparatus associated therewith.

\Vhat I claim is In a device of the class described, a nonconducting frame including end members and core members connecting sa d end members, binding posts carried by said end members res wctively, metallic rods connecting the end members and disposed above re spective core members, an insulated wire having one end connected to one of said binding posts and then coiled about said core members successively, the insulation of the coils disposed beneath respective rods being removed to expose the wire, sleeves sl-idablv mounted on each of said rods, contact fingers carried by the sleeves respectively, each of said fingers being U-shaped and having its outer arm extending substantially parallel to the adjacent coil and engaging'the exposed portion of the latter throughout the greater portion of the extent of said arm and having its side edges in engagement with the the adjacent removed portion of the insulation whereby the finger is guided in its movements, and an electrical connection between each of said rods and the other binding post.

In testimony whereof, I afiix my signature, In presence of two witnesses.

FORREST G. THACKABERRY.

Witnesses:

J. H. CAIN; P. A. MCMILLAN.

walls formed by 

